I have a few dozen. My original two kickstarters are still running but they very rarely are triggered. One I got soon after the kickstartedr is in my mailbox which is triggered at least six times a week. It still has the original batteries. Yet others have exhausted batteries in just a few months. Some cameras drain batteries more than others. I shuffle them around so those draining the most I plug into a power source.
I think the mailbox unit has lasted so long because the events are spread out and somewhat regular. Cameras in high traffic areas exhaust rather quickly. Again, the more spread out the events the better in my opinion.